Assigning and Testing Function from Structure of Uncharacterized Proteins

In 2000, the National Institutes of Health initiated the Protein Structure Initiative as a multi‐center structural biology program with “an initial goal to make the three‐dimensional, atomic‐level structures of most proteins easily obtainable from knowledge of their corresponding DNA sequences.” The third and final phase of this program concluded in 2015 with the publication and distribution of more than 5000 previously uncharacterized proteins. The work described here leverages the availability of high‐quality structures and pre‐cloned expression plasmids to combine forces of undergraduate biochemistry teaching lab courses across a diverse range of participating institutions. This consortium of undergraduate biochemistry faculty and students seeks to identify functional properties of a subset of these uncharacterized proteins, seeking to unify structure□ and □function relationships. Through structural and bioinformatics tools, an number of these proteins were characterized as putative hydrolases due to similarity to known hydrolase enzymes. Some appeared, by sequence homology, to possess features indicative of more specifically identifiable activity, such as halogenases and nucleases. Students in the current biochemistry laboratory class at Hope College have expressed and purified seven of these proteins, finding that structural information can guide, although not predict entirely, functional predictions regarding substrate specificity. Support or Funding Information This work was funded in part with support from the National Science Foundation IUSE program.